With the trend that we're seeing now, it's very likely that there'll' be a day within this century that there''ll be no ice in the arctic.

There's been a drastic change from the 1980s to the early 1990s to the present, the perennial ice cover in the 1980s was averaging between 7 and 8 million square kilometers. In 2007 when there was this drastic decline, it went down to as low as 3.5m square kilometers, and in 2012 it went down to almost 3 million square kilometers.

Compared to previous editions of the atlas, the change in sea ice coverage, that graphic portrayal, that white polygon, has significantly changed over time. And in the 10th edition atlas you'll see a significant reduction in area covered by ice.

Rosemary WardleySenior GIS CartographerNational Geographic Maps

On our arctic ocean plate we show two features of the different type of sea ice; there's the limit of multiyear ice and then the maximum extent of sea ice. The maximum extent of sea ice will fluctuate annually with the seasons, it generally decreases in the summer and increases in the winter and so the maximum that we show usually occurs sometime around March.

Multiyear ice is ice that has been frozen for up to two summers, and that is generally more stable and doesn't change as much but the studies have shown that it has been steadily decreasing over the past decade.